The present invention is directed to an apparatus for filling liquid into containers, such as bottles, subject to counter pressure. The liquid is located in a vessel with a liquid outlet channel at its base. The liquid is introduced into the vessel through its top. A valve seat is located at the liquid outlet channel and a valve body is located in the vessel and cooperates with the valve seat in forming a closure of the liquid outlet channel. The valve member is movable in the upward direction under spring loading. A spring encircles the valve body within the vessel and during pressure equalization between the container and the vessel affords compensation of the weight of the valve body which compensation initiates the automatic opening stroke.
Such filling apparatus are used, in particular, for filling liquids containing CO.sub.2 introduced from a pressure vessel into the bottle or other container connected with the filling valve. Pressure compensation between the bottle and the liquid vessel is achieved before the commencement of the filling step, so that the liquid flows into the bottle under a given head. During this process the gas contained in the bottle is displaced by the liquid into the gas space or the portion of the vessel located above the liquid level. For this purpose there is a gas return to which determines the end of the filling process as soon as the liquid reaches the lower end face of the tube. At this point an exchange of the gas back into the vessel is no longer possible. To compensate for the inherent weight acting on the filing valve body during pressure compensation, a compression spring is provided in valves of this type which assist in the opening process. A filling valve is of this type is disclosed in DE-OS 38 23 959. In this known arrangement, the spring affording pressure compensation is located below the liquid level in the vessel and rests at its lower end on appropriate abutments. The upwardly facing end of the spring rests against a protrusion on the movable valve body and assists its movement into the open position during the above described opening process.